Ruth Fremson/The New York TimesStealth troops of a new world order? New York State’s first lady, Michelle Paige Paterson, left, and fellow travelers along the West Side Highway bike path in June.

Could bicycling around the city for fun and transport have a more insidious purpose? Could it be that all these networked bike lanes, spreading across the nation’s cities like falling dominoes, are actually part of a vast conspiracy by the United Nations to take over America’s urban spaces, and in the process, take away our “freedom”?

The notion of such a nefarious bike plot, floated by one Republican running for governor of Colorado, has drawn puzzled reactions from cyclists in New York and beyond.

“First, Summer Streets, then, the world!” Bicycle Habitat, the Soho bike shop,posted to its Twitter account, referring to the annual event, which closes selected New York streets on consecutive Saturdays each August. (This year’s events begin this week.)

Nevertheless, bikes became an issue in the race for governor of Colorado after comments made by Dan Maes, one of three Republican candidates.

Mr. Maes accused the Democratic front-runner, Mayor John Hickenlooper of Denver, of instituting bicycle policies that turn the city into “a United Nations community.”

“This is all very well disguised, but it will be exposed,” Mr. Maes told supporters, and The Denver Post reported. Denver recently began a large-scale bicycle share program, known as B-Cycle; it is one of several cities around the country to do so in the last year. (New York’s own program remains in the planning stages.)

“These aren’t just warm, fuzzy ideas from the mayor,” Mr. Maes said. “These are very specific strategies that are dictated to us by this United Nations program that mayors have signed on to,” he said, referring to Denver’s membership in the International Council for Local Environmental Initiatives.

“When we heard the story, we all got a good chuckle,” said Martin J. Chavez, executive director of the organization and the former mayor of Albuquerque. “The next thought in the back of your mind is, ‘Gosh, I hope no one will actually believe that.’ ”

The organization, which is not part of the United Nations, has 605 member cities in the United States, including New York, and more than 1,200 worldwide, providing consulting and other guidance on sustainability.

“Maybe it’s a bit of Rocky Mountain high,” Mr. Chavez said.

A spokesman defended the Denver mayor’s efforts to encourage cycling, noting that the state of Colorado is among the least obese in the nation. “But equating our support of cycling in all its forms — road, mountain, commuting — with an international bike conspiracy is just ridiculous.”

Nate Strauch, a spokesman for Mr. Maes, stood by the candidate’s comments Wednesday, adding, “Something is wrong when cities and states and nations begin to cede their autonomy to extreme environmental organizations like Iclei.”

Mr. Maes is far from the first to lump cycling in with Volvos, universal health care and the World Cup as part of a plot to transform the United States into a Scandinavian socialist utopia. Indeed, the connection is an old one.

To take one example, in 1980, when New York was in the process of removing its new bike lanes amid protest, the conservative writer R. Emmett Tyrrell Jr.railed against “New York’s powerful cycling lobby,” accusing Mayor Edward I. Koch, who had implemented a bike lane the previous summer, of having become enamored with “crowds of smiling Maomen pedaling the streets” during a visit to China.

As for bike programs taking away freedoms, advocates like Caroline Samponaro at Transportation Alternatives saw a logical disconnect: “Bicycle transportation in cities epitomizes freedom,” she wrote, adding that the bike and pedestrian advocacy organization would rather keep its distance from Colorado politics, and from conspiracy theories.